1. drop by
e.g. Drop by at any time.
什么时候都可以来我这里.
e.g. Could I drop by this evening to pick up my Tao Bao items?
我晚上可以去你那儿上淘宝选几样东西吗？
language barrier 语言障碍

2. drop in
e.g. I will drop in your class later.
我一会儿来班上找你。
e.g. I will drop by your house.
我会来你家看你。
drop in 需要在同一个空间里

3. stop by
e.g. Do you mind if I stop by later today?
你介意今天晚些时候我去拜访你吗?
e.g. I stopped by the noodle restaurant, but you weren’t there.
我刚去了那家面条店，但是你没在。

4. come around
e.g. You can come around any time.
你什么时候来都行。
go around 指到处转转，不是串门儿的意思

5. come by
e.g. Should I come by your house today to pick up the gifts for the children?
我今天能来你家给孩子们选选礼物吗？
blow around 也不是串门儿的意思